Re: extracting a list to a list, help please

• To: mathgroup at smc.vnet.net
• Subject: [mg46192] Re: [mg46155] extracting a list to a list, help please
• From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
• Date: Tue, 10 Feb 2004 00:06:17 -0500 (EST)
• References: <200402091054.FAA20948@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

```On 9 Feb 2004, at 11:54, Serge wrote:

> Hello,
>
> I am a beginner in Mathematica and I have a rather simple question. I
> made some calculations that I need for an orbit and I have a list that
> look like this:
>
> mylist1 = {{a1,b1,c1,d1},{a2,b2,c2,d2},{a3,b3,c3,d3},etc}
>
> All I want to do is to make a list of the form
>
> mylist2 = {{a1,b1},{a2,b2},{a3,b3},etc}
>
> from the original list (mylist1),
>
> so that I can ListPlot those pairs of points (they represent x and y
> coordinates for some orbit). I am having trouble figuring out how to do
> this. I tried using the Table command but I couldn't get it into the
> above form. I would greatly appreciate if someone can help me out.
> Thanks so much.
>
> Best,
> Serge
>
>
>
This is the sort of thing that can be done in a lot of ways. Here are
just a couple:

mylist1[[All, {1, 2}]]

Map[Take[#, 2] &, mylist1]

Andrzej Kozlowski
Chiba, Japan
http://www.mimuw.edu.pl/~akoz/

```

• Prev by Date: Re: extracting a list to a list, help please
• Next by Date: Re: computation of autocovariance
• Previous by thread: Re: extracting a list to a list, help please
• Next by thread: Re: extracting a list to a list, help please